Free power unit converter · No sign-up · Runs entirely in your browser
Convert mechanical horsepower, brake horsepower, metric horsepower (PS), kilowatts and watts using exact conversion factors — plus a power-to-weight ratio in kilowatts per tonne.
Power-to-weight ratio
| Unit | Value |
|---|
Check whether your source says "hp" or "PS" before converting. Metric horsepower (PS, ch, cv) is about 1.4% smaller than mechanical horsepower, so a German "250 PS" is 246.6 hp — not 250. Getting this wrong is the most common error in cross-market vehicle comparisons.
Need power from torque and RPM rather than a unit conversion? Use the Engine Horsepower Calculator.
In Australia, vehicle power is officially rated in kilowatts (kW). However, horsepower (hp) is still widely understood. Most Australian car manufacturers list both kW and Nm (Newton-metres of torque).
| Vehicle type | Typical power |
|---|---|
| Small city car | 60–90 kW (80–120 hp) |
| Family sedan | 110–150 kW (150–200 hp) |
| Performance sedan | 200–300 kW (270–400 hp) |
| V8 ute/SUV | 230–270 kW (310–360 hp) |
This is a power-unit converter. Enter a figure in any unit — horsepower, kilowatts, metric horsepower, watts, BTU per hour or foot-pounds per second — and it returns the equivalent in all the others, plus a power-to-weight ratio if you want one.
It exists because the same engine is described by three different numbers depending on which market is doing the describing. An Australian brochure says kilowatts. A British magazine says horsepower. A German specification sheet says PS. Nothing about the engine changes; only the arithmetic does.
All of these measure the same physical quantity — the rate of doing work. They differ only in size and in which part of the world uses them.
| Unit | Symbol | Value in watts | Used in |
|---|---|---|---|
| Watt | W | 1 W (SI base) | Physics, electrical, small motors |
| Kilowatt | kW | 1,000 W | Australia, NZ, EU official ratings |
| Mechanical horsepower | hp, bhp | 745.70 W | UK, USA |
| Metric horsepower | PS, ch, cv | 735.50 W | Germany, France, Italy, Japan |
| Foot-pounds per second | ft-lb/s | 1.3558 W | Imperial engineering |
| BTU per hour | BTU/h | 0.2931 W | Heating, cooling, HVAC |
| Factor | What it represents |
|---|---|
| 0.7457 | Watts in one mechanical horsepower, divided by 1,000 |
| 0.7355 | Watts in one metric horsepower, divided by 1,000 |
| 1.341 | Reciprocal of 0.7457 — horsepower per kilowatt |
| 1.3596 | Reciprocal of 0.7355 — PS per kilowatt |
| 0.9863 | Ratio of metric to mechanical horsepower |
A car is advertised locally at 150 kW.
| Convert to | Calculation | Result |
|---|---|---|
| Mechanical horsepower | 150 × 1.341 | 201.2 hp |
| Metric horsepower | 150 × 1.3596 | 203.9 PS |
| Watts | 150 × 1,000 | 150,000 W |
If an overseas review of the same car quotes 204 rather than 201, the reviewer is almost certainly using PS. Both numbers describe an identical engine.
A US-market car is advertised at 300 hp. To compare it against Australian listings:
That places it between a large performance SUV and a genuine sports car in Australian terms. Worth noting: US figures are usually measured to SAE J1349, which applies its own temperature and pressure corrections, so a directly comparable Australian figure for the same engine may differ slightly even after conversion.
A German car is listed at 250 PS.
| Convert to | Calculation | Result |
|---|---|---|
| Kilowatts | 250 × 0.7355 | 183.9 kW |
| Mechanical horsepower | 183.9 × 1.341 | 246.6 hp |
An electric motor is rated at 75 kW.
The arithmetic is identical to a petrol engine — a watt is a watt. What differs is delivery:
| Type | Peak power arrives | What that means when you read the spec |
|---|---|---|
| Petrol | High in the rev range | You have to reach for it — a downshift is often required |
| Diesel | Low-to-mid, with strong torque earlier | Feels stronger than the number suggests when loaded or towing |
| Electric | Effectively from standstill | Feels quicker than the number suggests in traffic and off the line |
This is why converting two figures to the same unit tells you they are equal on paper, but not that they will feel equal. A 75 kW EV and a 75 kW petrol car have identical peak output and quite different characters.
| Kilowatts | Mechanical hp | Metric PS |
|---|---|---|
| 50 kW | 67 hp | 68 PS |
| 75 kW | 101 hp | 102 PS |
| 100 kW | 134 hp | 136 PS |
| 110 kW | 148 hp | 150 PS |
| 150 kW | 201 hp | 204 PS |
| 200 kW | 268 hp | 272 PS |
| 250 kW | 335 hp | 340 PS |
| 300 kW | 402 hp | 408 PS |
| 400 kW | 536 hp | 544 PS |
For rough mental arithmetic, kilowatts × 1.34 is close enough for horsepower, and horsepower × 0.75 gets you back to kilowatts.
Local specifications, converted. These are current Australian figures as at July 2026 — useful both as a sanity check on your own conversions and as a sense of scale.
| Vehicle (Australian spec) | kW | hp | PS |
|---|---|---|---|
| Toyota Corolla Hatch Hybrid 1.8L | 103 kW | 138 hp | 140 PS |
| Toyota HiLux 2.8L turbo-diesel | 150 kW | 201 hp | 204 PS |
| Ford Ranger 2.0L bi-turbo diesel | 154 kW | 207 hp | 209 PS |
| Ford Ranger 3.0L V6 turbo-diesel | 184 kW | 247 hp | 250 PS |
| Toyota GR Corolla 1.6L turbo | 221 kW | 296 hp | 300 PS |
| Heavy truck (prime mover) | 300–450 kW | 402–603 hp | 408–612 PS |
This is the source of most confusion, and one of the four is not what people think it is.
| Term | What it actually means | Same size as hp? |
|---|---|---|
| hp | Mechanical horsepower, 745.7 W | — |
| bhp | Horsepower measured at the flywheel using a brake dynamometer | Yes — identical |
| PS | Metric horsepower, 735.5 W | No — about 1.4% smaller |
| kW | SI unit, 1,000 W | No — 1 kW = 1.341 hp |
Even after you have the units right, the same engine can post different figures depending on which test standard produced them. Power is measured under controlled conditions, and the standards disagree about what those conditions should be.
| Standard | Origin | Notes |
|---|---|---|
| SAE J1349 | United States | Net power with production accessories fitted; applies its own temperature and pressure corrections. A certified-testing option exists, marked "SAE Certified Power" |
| DIN 70020 | Germany | Net power, long the basis for European PS figures |
| ISO 1585 | International | Net power; widely referenced across Europe and beyond |
| JIS | Japan | Japanese domestic testing standard |
In practice the differences between current net standards are small — a few per cent at most — but they are real, and they sit on top of any unit-conversion error. If two sources disagree about a car by a small margin and you have already ruled out hp versus PS, differing test standards are the usual explanation.
Manufacturers quote power at the flywheel. A chassis dynamometer measures it at the driven wheels, after the gearbox, differential, driveshafts and tyres have taken their share.
| Drivetrain | Typical loss | 200 kW at the flywheel reads roughly |
|---|---|---|
| Front-wheel drive | 10–15% | 170–180 kW |
| Rear-wheel drive | 15–18% | 164–170 kW |
| All-wheel drive | 20–25% | 150–160 kW |
Australia metricated in the 1970s and adopted SI units across engineering and regulation. Vehicle power has been officially expressed in kilowatts ever since, and that is what appears on compliance documentation and in local specifications.
Horsepower has not disappeared, though. You will still meet it in:
| Vehicle type | Typical power | In horsepower |
|---|---|---|
| Small city car | 50–90 kW | 67–121 hp |
| Family hatchback or sedan | 90–150 kW | 121–201 hp |
| Medium SUV | 110–190 kW | 148–255 hp |
| Dual-cab diesel ute | 110–190 kW | 148–255 hp |
| Performance car | 250–450 kW | 335–603 hp |
| Road motorcycle | 25–150 kW | 34–201 hp |
| Heavy truck (prime mover) | 300–450 kW | 402–603 hp |
| Electric passenger car | 100–400 kW | 134–536 hp |
| Industrial electric motor | 0.5–500 kW | 0.7–670 hp |
Indicative ranges only. Check the manufacturer's current specification for any particular model — figures change between model years and variants, and vehicle mass, gearing and torque delivery matter as much as the headline number.
Power alone tells you very little. Divide it by mass and the picture sharpens immediately.
| Same engine, different car | Calculation | Result |
|---|---|---|
| 150 kW in a 1,300 kg hatchback | 150 ÷ 1.3 | 115 kW/tonne |
| 150 kW in a 2,500 kg SUV | 150 ÷ 2.5 | 60 kW/tonne |
Identical power, and the hatchback has nearly twice the ratio that actually predicts acceleration. This is why a modest engine in a light car often feels quicker in traffic than a powerful one in something heavy, and why loading a vehicle blunts it noticeably without touching the engine. You do not need a separate tool for this — the power-to-weight section of the calculator at the top of this page does it directly. Enter power in kilowatts and kerb mass in kilograms, and it returns kilowatts per tonne, the figure Australian comparisons normally use, alongside watts per kilogram and horsepower per pound.
How do I convert horsepower to kilowatts?
Multiply horsepower by 0.7457. A 300 hp engine is 300 × 0.7457 = 223.7 kW. If the source quotes metric horsepower (PS) rather than mechanical horsepower, multiply by 0.7355 instead.
How many kilowatts are in one horsepower?
One mechanical horsepower is 0.7457 kilowatts, or 745.7 watts. One metric horsepower (PS) is 0.7355 kilowatts, or 735.5 watts — slightly less.
How many horsepower are in one kilowatt?
One kilowatt equals 1.341 mechanical horsepower, or 1.3596 metric horsepower (PS). For quick mental arithmetic, multiplying kilowatts by 1.34 is close enough for most purposes.
What is the difference between hp and kW?
They measure the same thing — the rate of doing work — in different units. The kilowatt is the SI unit and what Australia uses officially. Horsepower is an older imperial unit still standard in the UK and USA. One kilowatt is 1.341 horsepower.
Is bhp the same as hp?
Yes, in size. Brake horsepower and mechanical horsepower are both 745.7 watts. The word "brake" refers to the braking device a dynamometer uses to load the engine, so bhp signals that the figure was measured at the flywheel rather than at the wheels. There is no conversion factor between hp and bhp.
What is metric horsepower?
Metric horsepower is a continental European unit equal to 735.5 watts, defined as the power needed to lift 75 kilograms one metre in one second. It is about 1.4% smaller than mechanical horsepower, so the same engine posts a slightly higher number in PS than in hp.
What does PS mean in car specifications?
PS stands for Pferdestärke, German for horse strength, and denotes metric horsepower. French listings use ch and Italian ones cv for the same unit. If a specification comes from Germany, France, Italy or Japan and quotes a horsepower-style number, it is usually PS rather than mechanical hp.
Why does Australia use kilowatts instead of horsepower?
Australia converted to the metric system in the 1970s and adopted SI units across engineering and vehicle regulation. Power has been expressed in kilowatts in local specifications ever since. Horsepower still appears in imported vehicle listings, motorcycles, marine engines and small machinery.
How do I convert watts to horsepower?
Divide watts by 745.7 for mechanical horsepower, or by 735.5 for metric horsepower. A 2,200 W appliance motor is 2,200 ÷ 745.7 = 2.95 hp. Going the other way, multiply horsepower by 745.7 to get watts.
What is wheel horsepower?
Wheel horsepower is measured at the driven wheels on a chassis dynamometer, so it reflects what actually reaches the road after drivetrain losses. It typically reads 10–15% below the flywheel figure on front-wheel drive, 15–18% on rear-wheel drive and 20–25% on all-wheel drive. Converting units will not reconcile a wheel figure with a manufacturer's flywheel claim.
Does more horsepower mean a faster car?
Not on its own. Acceleration depends on power relative to mass, so a 150 kW car weighing 1,300 kg will out-accelerate a 150 kW vehicle weighing 2,500 kg by a wide margin. Gearing, tyre grip, aerodynamics and where the torque arrives in the rev range all matter too.
How much horsepower does an electric motor produce?
Electric motors are normally rated in kilowatts and convert exactly as any other power figure does — 75 kW is 100.6 hp. Passenger EVs commonly range from about 100 kW to over 400 kW, while industrial motors span a fraction of a kilowatt to several hundred. Because electric motors deliver near-peak torque from standstill, they often feel stronger than an equivalent petrol figure suggests.
Horsepower, kilowatts, PS and watts all describe the same physical quantity, so the arithmetic is never the hard part. What matters is knowing which unit your source is using, whether the figure was taken at the flywheel or the wheels, and under which test standard. Get those three right and cross-market comparisons become straightforward.
Power is also only one input into a buying decision. Weigh it against mass, torque delivery and what the vehicle will actually cost to run — check consumption with the gas mileage calculator, price the fuel with the fuel cost calculator, and if you want power from torque and RPM rather than a unit conversion, the engine horsepower calculator handles that.